1. Field of the Invention
This invention relates to a combination lamp, such as a vehicle combination front light.
2. Description of the Prior Art
In general, discharge lamps are superior in efficiency and luminance to filament lamps. A light emitting tube of the discharge lamp produces inadequate luminous energy at low temperatures. The luminous energy from the light emitting tube is acceptable at high temperatures.
Some automotive headlights include discharge lamps. Japanese published unexamined patent application No. 60-84702 discloses an advanced headlight of this type. In this advanced headlight, heat insulating members serve to reduce the rate of the escape of heat from the light emitting tube in a discharge lamp. The reduction of the heat escape rate speeds up increases in the temperature of the light emitting tube after the discharge lamp is turned on. Accordingly, the light emitting tube can produce adequate luminous energy within a shortened time after the discharge lamp is turned on.